Piston construction



Oct. 13, 1925. 1,556,634

J. H. RYALLLS med Au. 26. m4

Patented Oct.v 13, 1925.

UNITED STATES 1,556,634 PATENT oFFlcs.

JOHN H. RYALLS, F CHARLOTTESVILLE, VIRGINIA, ASSIGNOB. 0Fv ONEJIHRD T0 L. G. HOXTON' AND ONE-THIRD TO CEAS. H. PAGE, BOTH OF. CHABLOTTESV'ILLE.

VIRGINIA'.

PISTON CONSTRUCTION.

Application med August 26, 1924. Serial No. 784,323.

To all whom t may coa-cem.

Be it known that I, JOHN H. RYALLs, a

i citizen of the United States, residing at Charlottesville, in the county of Albemarle and State of Virginia, have invented certain` new and useful Improvements in Piston Constructions, of which the following is a specification.

This invention relates'to improvements inv the construction of bustion engines.

An object of the inggition resides-in pro-v viding a piston con ruction for internal combustion engines having removable cylinder heads, which are constructed to adapt the removal of the piston from thecylinder and the disconnection of the piston pin bearing from the upper end of the cylinder block by merely removing the cylinder head.

Another object of the invention resides in providing a piston construction, wherein the skirt portion of the piston and the ring carrying portion are formed integral and rovided at the upper end with an annular shouldered recess with which communicates a portion of small diameter, which is screw threaded for the reception of a threaded` flange projecting from a shoulder portion on the piston cap, which is adapted to seat in the shouldered end of the skirt portion of the piston, and which is provided with set lscrews threadedly mounted in the cap portion of the piston and having reduced extensions for engaging in suitable openings formed vin the shouldered portion of said piston, said screws adapted to prevent said'cap portion` from rotating in the head of the piston 'and becoming disengaged therefrom, while the same is in operation in the cylinder, said cap forming the' piston head and the active surfaces on which the gases of combustion act to guide the piston in the cylinder, and which, upon 'remova from the skirt portion permits the removal of the upper section with a sectional bearing used in connection with the wrist pin in the skirt portion of the piston, so that said skirt portionmay be removed from the cylinder by merely removing the cylinder headand the'cap of the piston.

The 'invention further includes other objects and -improvements in the construction and assemblage of the parts as well as the specific formation thereof, lwhich are more particularly pointed out in the iollowing pistons for internal comdescription and claim, directed to a preferred form of the invention, it being understood, however, that variations may be made in this specific construction and arrangement of parts without departing from the spirit and scope of the invention as described and claimed.

In the drawing, forming a part of this appllcation:

Figure the piston constructed accordingl to this invention.

Figure 2 'is a plan view of the piston. Figure 3 is a plan view of the skirt por- 1 is an enlarged sectional view of 65 tion of the piston showing the cap portion removed therefrom.

Figure 4 is a detail view of the improved connecting rod used with the improved piston construction.

The piston is indicated generally at 7 and 75 as constructedaccording to this invention is connected to the usual connecting rod 12, which is connected to suitable bearings on the `crank shaft 13 which are mounted for engine 1n a well known manner. The piston 7 has ,a skirt portion 14, which is formed to receive a plurality of piston rings 15, in the piston ring grooves formed therein in the usual manner, and which is provided in the central portion with inwardly directed cylindrical portions 16, which receive and mount the usual wrist pinsl 17 therein, against rotation. The upper end of the sleeve is formed with an inwardly annular flange 418, which is screw threaded as at 19, on the inner which is formed at 20 with an annular shoulder and a portion of enlarged diameter extending through the upper end of the 9 piston.v The piston Acap or head 2 1 is of annular form and has a diameter equal to l the diameter of the slkirt'portion 14, and is portion ofthe .skirt 14 of the piston. The

reciprocating action in the cylinder of the 8 surface thereof, andh directed thereof, which piston skirt 14 is provide 2 msdos-i piston head 21 and the shoulder portlon 23 thereof, in order that these screws may be inserted into the piston head with the extension 27 seated m the opening 26 in the skirt portion of the piston, for preventing the piston head from rotating therein, when secured in lace. This assemblageof the parts is clear y shown in Figure 1, and

it will be Areadily appreciated that after the engine, in which this. piston .is mountedhas been runfor a short length of time, that the f carbon forming onathe upper surface of the piston head will form overy the screws and in the slot therein; and etectively lock the same against movement. in the piston headl or cap portion, so that thereafter the cap portion isheld in place and against rotation in the skirt portion 14, regardless of any difference of expansion due to the difference of heating of the various portions of the piston andthe head and the severance of the cad portion and the skirt portion thereby prevented.

The cap portion of the'pisiton is lprovided at 30,`w1th recesses thereln adapted to receive a suitable wrench, for applying and removing said cap portion from the skirt portion whenA the piston is assembled or disassembled on the engine and in the cylinder,

inlorder to remove the skirt portion there-` from. A special connecting rod construetion is provided in connection with thisv iston construction, which is shownY at.12, in igure 4, and is formed at the upper end with a half bearingl 32, with which cooperatesfa half bearing 33 carried by a suitable vremovable bearing member 34, whichis secured tothe main portion of the connectin rod by suitablebol 35,- in the usual we known manner. f 1 Y With an engine constructed according to this invention, it will be. readily. seen that the piston may be entirely yremoved f rom vthe cylinder b 'removing the c linder head therefrom andy then removin th and the head- 21 from the e screws 281- l rtpportion 14; which' provides to the'bolts 3 5 securing the' removable section '34 tothe connecting rod, andl which, upon-removal,

Will permit the removal of the skirt portion of the cylinder, so that new piston rm `or a new piston may be placed 1n the cyhnder and all other operation desired `may be a plied t epeto, 'and at the same time may placed in the cylinder without removing .the bearingy connection of the connecting rod with the crankshaft or any of the associated parts which .provide access to the crank shaft, and which exceedingly simplifies the construction ofan'internal combustion` en- 70 glnel to ermit the repair and replacement of the piston constructions and parts thereof, with a minimum time and at a minimum cost, 'and-)upon the removal of a very few parts. l

From the above description, it should be readil appreciated that a relatively sim le and e cient'constr'uction has been provi ed for internal combustion engines, wherein the cap portion is readily removable, in. order to permit the pistons removal from the oylinder, without removing the connectng rod bearing from the crank shaft, and which provides a Vrigidly interlocked y 'structure when the parts are secured in assembled re- .v

lation.4

What is claimed is:

A' piston comprisin 'a' skirt porti-dn'Y formed with wrist pin arings intermediate the ends, the upper end lof said skirt portion being formed with -an inwardly directed annular flange havingl'the inner peripherg7 screw threaded and formed with fa shoulder on the upper end,'the upperend of the skirt portion bein formed with' an internal diameterof en arged size above said shoulder portion extending' thrdugh the upper end of said skirt portlon', a cap ha vlng. an'external diameter` equal to that" of the skirt portion, and anA annular projection of leo reduced 4diameterto fit the enlargeddiame-A ter ofthe upiperv end of the skirt portion,'-

extension from saidannuflar and a' reduce projection of reduced diameter and" threaded for` cooperation with the threaded por-' A1mi tion ofthe flange ofthe skirtportionfand A.locking screws adapted lfor threaded coop- -eration with the cap portion', and projecting into openings in the flange of the skirt 'no' portion for locking said cap portion after threaded'application on the skirt portion against movement thereon.

v In'testimony whereofl afiix my signature.

JOHN, H.' entre. 

